The website is complicated by the need to choose from several guided tours. Can't I wander aimlessly looking at the architecture without a guide? If not, which tour is the best? Also, I'm going in a couple weeks during a weekday. Do I have to get a reservation, or can I just show up and expect to take the next tour without too much hassle. Any other tips on getting the most from this visit would be appreciated. I'm a native Californian who for some reason has neglected to see this monument.